Derrick



(No Model.)

M. S. HILDRETH.

DERRICK. No. 430,207. Patented June 17, 189 0.

J I g I, 1 8

3 3I 17 i z 7 zizz rzcsses w kzem tor:

nnnnnn ms Parana cm, mow-mum. WASHINGTON, n. c.

UNITED STATES ATENT OFFICE.

DERRICK.

SPECIFICATION forming part of Letters Patent No. 430,207, dated June 17,1890.

Application filed March 21, 1890.

To all whom it may concern:

Be it known that I, ll/IICHAEL S. HILDRETH, residing at Grand Junction,in the county of Mesa and State of Colorado, have invented a new anduseful improvement in derricks for theconstruction of a flume, tramway,or simiilar structure along a nearly perpendicular wall of rock, ofwhich the following is a specification.

My invention relates to a derrick to be used in the construction offlumes, tramways, or similar structures along a nearly perpendicularwall of rock when the brackets supporting the structures are too highabove the base of the rocky wall to be secured in place by ordinarymeans; and the objects of my invention are, first, to provide a derrickwhich may be readily moved forward as each bracket is secured in place;second, to provide means for securing the derrick rigidly and firmly tothe brackets without the use of guy-ropes, and, third, to provideplatforms on which the workmen may stand while putting up the brackets.I attain these objects by means of the mechanism'shown in theaccompanying drawings, in which Figure 1 is a side view of the derrick,and Fig. 2 is a top view.

Similar figures refer to similar parts in both views.

The derrick proper consists of two timbers 3, fastened together at oneend by a bolt 4, and opening out at the other end like the letter V.These timbers are long enough to rest upon three or more of thebrackets, and extend out beyond the point where the; next bracket is tobe attached to the rocky wall. Platforms 5 and 6 are supported from theprojecting and open end of the timbers 3 by ropes or rods 7, and areoccupied by the workmen when drilling holes and securing the brackets inplace. A movable carriage 8 10, in connection with the permanentstringers 9, all resting on top of the brackets 2, serve as a supportfor the derrick and for moving it forward as each bracket is secured.The

carriage consists of two parallel pieces of timber S, of the same sizeas the stringers 9, secu rely joined together by the cross-pieces 1O 10,the carriage being made narrower than the space between the stringers 9.

The derrick is supported on a roller 24, which is long enough to extendout over both erial No. 344,817. (No model.)

of the stringers 9. Two posts 11 and 12 are framed to the cross-pieces13 and 14, which are secured at each end in boxes 17. Stay ropes or rods18 serve to raise the posts to the desired position and to hold themfirmly in place, while the braces 15 and 16 prevent any side swaying.Suitable blocks and tackle l9, suspended from the post or boom 11, areused for raising or lowering timbers, 850. Two iron hooks 20 are securedto the roller 24, and are of a suitable length and shape to engage theunder side of the horizontal timber 2 of the bracket when the roller 24is nearly above the timber. After the hooks 20 have been hooked to thetimber 2, if the derrick be drawn backward a little the grasp of thehooks upon the timber will be tightened and made very firm and secure,and the rear end of the derrick is then tied by a rope or chain 21 tothe bracket just underneath it. The derrick is thus secured firmly andrigidly without the aid of guy-ropes, and is in position for use inputting up the next bracket, which is the position shown in thedrawings.

To move the derrick forward after the bracket is in place, the rope orchain 21 is loosened and the machine moved forward far enough todisengage the hooks 20 from the timber 2. Two tapering strips or wedges22 are now placed on top of the stringers 9 and the machinerolledbackward, raising the roller 24 entirely above thecarriage-timbers 8, when the entire carriage may be pushed ahead untilthe front end rests upon the new bracket. The stringers may now be putin place and the derrick rolled forward and secured as before.

Having thus described my invention, what Iclaim as new, and desire tosecure by Letters Patent, is

1. The combination, with the V-shaped derrick-frame 3, of the roller 24,hooks 20, posts 11 and 12, and suspended platforms 5 and 6, all arrangedand operating substantially as and for the purposes specified.

2. The combination, with a portable derrick mountedon a roller 24, ofthe carriage 8 10, stringers 9, and wedge-shaped pieces 22,substantially as and for the purpose specified.

MICHAEL S. HILDRETH.

Witnesses:

WILLIAM J ACK, ABEL M. LAYTON.

